Yarn traversing mechanism for knitting machines



K. HOWlE 2,780,083

YARN TRAVERSING MECHANISM FOR KNITTING MACHINES Feb. 5, 1957 2 Sheets-Sheet 1.

Filed Dec. 18, 1953 INVENTOR flew/167% Haw/e ATTORNEY K. HOWlE Feb. 5, 1957 YARN TRAVERSING MECHANISM FOR KNITTING MACHINES 2 Sheets-Sheet 2 Filed Dec. 18, 1953 INVENTOR ATTORNEY YARN TRAVERSING MECHANISM non KNITTING MACHINES This invention relates to knitting machines of the type disclosed in my prior U S. Patent No. 1,982,991, for example, and aims generally to improve the yarn traversing mechanism of such machines.

Particular objects of the invention, severally and in terdependently, are to facilitatethe replacement of the flexible bands that drive the yarn carriers in such machines when they become broken; 'to greatly increase the life of such bands; to prevent or reducerebound of the mechanism from the positioning stops; to. prevent flying coupling and/or dog carriers fromdarriaging' the machine when a band breaksjto enable the speed of the machine to be increased without danger of more damage from.flying coupling and/or dog carriers; to enable the bands to be run more loosely than in the previous machine, reducing the sharpness of the bends around the guide rollers, thus further increasing the life of the bands; and to provide means to aid in causing proper engage ment of the band driving dog means with the associated driver independently of the dog means being held upright by a tightly drawnband.

The bands of the machine of my aforementioned patent on the average would run about two months before breaking. They had to be stiff enough and be drawn tightly enough to support the band mounted dog carriers in position to be engaged by the driver elements. Therefore bands about A wide and about 0.0055 thick were used. Several sets of guide rollers at one end of the machine were released and moved inwardly to enable the bands to be inserted, and were then drawn outwardly to tensionthe bands sufficiently to insure that the dog means would stand vertically and be engaged by the driver pawls. The two months average service life of such bands corresponds to a life of about three minutes on an accelerated testing machine.

By contrast, with the present arrangement the bands need not be put under strong tension and do not themselves have to hold the dog means erect in position to engage with the driver pawls, hence thinner and relatively slack bands may be used. For comparison where a band of 0.0055" thickness will last three minutes on the .accelerated testing machine, a band of 0.004 thickness Will last 6 to 8 minutes under the same test, and a band .of 0.002" thickness will last eighteen hours on the same machine. In actual use, where the 0.0055" band had a two months average service life, with the present improvement a machine having seven bands, operating twenty-four hours a day, six days a week, for a year, suffered only two broken bands. Furthermore, the replacements of these bands were effected in a fraction of the time required to replace the bands of the previous machine, with the result that shut down timedue to breakage of bands was almost completely eliminated by the present improvements.

In addition to the objects and advantages above referred to, the invention contemplates the provision of a simple and efiective construction and tool to aid in the positioning and joining of the band ends to the band nited St P atefif-G that will be apparent from the foll'owing description of coupling rneans, as well as other objects and advantages an illustrative embodiment of the invention. The invention resides in the new features of construction and novel elements and combinations hereinafter described and is more particularly pointed out in theappended claims.

bodiment:

In the accompanying drawings of the illustrative em Fig. 1 is a more or less diagrammatic plan viewlof.

the yarn traversing arrangement.

Fig.2 is'an enlarged detail in plan of a part of'the positions.

Fig. 3' is a side elevational detail of a coupling and dog carrier with'associated band ends and means for supporting the coupling and dog carrier.

Fig. 4 is a vertical section taken on the line 4-4 of Fig. "3 looking in thedirection ofthe arrows.

Fig. 5 is a perspective view of oneof the band ends supported by an assembly assisting tool.

Fig. 6 is an edge elevation of the, tool.

Fig. 7 is a disassembled perspective of a suitable form of yarn laying tube and carrier; and

Fig; 8 is a vertical cross-section thereof.

Referring now to the illustrative embodiment shown in the drawings, the tubularthread guides 2 (Figs. '7 and 8) are mounted one on each of the thin steel flexible bands 26 (Figs. 1'-3), say for instance, seven in number in the particular machine shown. The thread guides t are held in place frictionally in tube holders t2 (Figs. 1, 7 and 8) shown in the form of thin plates riveted tothe bands 26 intermediate their couplable ends, and tapered at eachend toward the plane of'the band, the tube holder assembly having a vertical aperture t3 therethrough (Fig. 7) for frictionally retaining the yarntube, such aperture preferably being formed by notching the rear face of the plate t2 so that the tube 2. is gripped between the platetZ and the band 26 (Figs. 7-8), the construction assuring a firm, easily released securement. The bands 26,as shown in Figs. 3 and 5, are not endless, but are provided at their endswith downwardly opening undercut coupling hooks 26a formed in two thin reinforcing plates 26b that are secured on either side of the band end as by riveting thereto, the hooks 26a being engageable with pins 34a extending transversely of slots 34b formed in the ends of the'dog and coupler carriers, 34,

shown in Figs. 3 and 4 comprise a coupling portion 340 having slotted ends 34b (Figs. 2 and 3) for receiving the hooked ends 26b of the bands, and bridged by transverse pins 34a (Fig. 3) engaging in the undercut hooks 26a as aforesaid. The ends of the coupling portion are tapered toward their tips as best shown in Figs. 2 and 3. Downwardly projecting from the coupling portion 340 is a dog portion 34d (Figs. 3 and 4) that has inclined ends 34e for engagement by the driver pawl (not shown, but which in general may resemble the driver pawl 31a ofFig. 9 of my aforesaid Patent No. 1,982,991) that drives the coupling and dog carrier to its associated stop and is then cammed downwardly by the inclined end Me and passes under the dog 34d. In the form shown, the entire dog 34d, 34a is positioned below the lower edges of the band ends when the latter are connected by, the coupling and dog carrier. I

Upstanding from the coupling portion 340 is a supporting web 34 provided with a runner shown as compris ing oppositely extending flanges or shoes 345 that engage in grooves of guide rails 40 hereinafter described, and

rammed Feb. 5, .1957.

but which may correspond generally to stops RS etc., in Fig. 9 of my aforesaid patent), abutment means 37 for engaging the 'home stops (not shown but which may be generally similar to the stops H, Fig. 35 of my aforesaid patent), and detent element means 38 for engaging cooperating detent element means 39 (Fig. 2) for releasably retaining the coupling and dog carrier against the home stop therefor.

In the arrangement shown the abutment means 35 are provided by a web 35a extending above the flanges 34g and aligned with the web 34f, which may further cooperate with the guide rails hereinafter described, to aid in insuring an erect position of the coupling and dog carrier at all times; thus affording a strong and simple construction.

The home-stop abutments 37 in the form shown are afforded by the ends of the Web 34f, 35a embraced between the runner elements 34g, and laterally backed up thereby. The detent element means 38 is provided in the form shown by notching the edges of one of the runner elements adjacent the ends thereof, and beveling the extremities of the said runner as shown at 3811 (Fig. 2) to facilitate its depression of the cooperating detent element 39 (Fig. 2) more fully described hereinafter.

In the form shown it will be noted that while only one of the runners is notched at 38 adjacent its ends, the unit 34 as a whole is reversible, so that the same unit 34 may be used with cooperating detent means located either outside or inside of the unit as seen in Figs. 1 and 2, which shows a part of the upper left hand end of Fig. 1 to an enlarged scale.

The guide rails 40, in the form shown in Figs. l4, are comprised of light relatively flexible channelled members and are supported just above the bands 26 by supporting arms 41 (Fig. 1) so that they provide running spaces between them extending between the home stops for each coupling and dog carrier 34, the arms 41 being in turn supported from a frame portion of the machine by a suitable mounting 42. In the form shown, the intermediate guide rails 40 are I-shaped in cross section, the flanges thereof being spaced to accommodate the webs 34f, 35f between them, and the rail webs being spaced to accommodate the runners 34g. The inner and outer rail members may be of like construction but as they need be channelled only on one side, they may take the form of C-channels as shown.

Thus, when the rail members 40 are not flexed out of their normal position they support and suspend and guide thecoupling and dog carriers 34 and maintain them in true alignment with their driving pawls and endand homing-stops, above described. However, when it is desired to remove or replace a band 26 or its coupling and dog carrier 34, such replacement may be readily effected by moving the unit to be replaced to a position somewhere near the center of the rail length, while the other units 34 are held near the end thereof, whereupon the flexible rails may easily be sprung apart to release the runners 34g and enable removal of the unit, or insertion of another unit 34.

Because the units 34 are supported and guided in operation by the rails 40, it is not necessary to tightly tension the bands 26 to hold them upright. Therefore the bands do not have to carry as much tension and can be made lighter. Further, the relaxing of the band tension avoids the production of relatively sharp bends in the bands about the rollers 27 and allows the bands to follow a relatively gentle curve about the rollers without substantial straightening from roller to roller. This reduction of the amount of flexing of the bands, coupled with the lesser thickness and lesser tension thereof, triply reduces the strains of flexure and contributes to the greatly increased life of the bands. At the same time, the absence of high band tension and the guidance of the units 34, prevents flying of said units into moving parts of the machine on the infrequent occasions in which breakage of a band may occur.

As clearly shown in Figs. 24, in the illustrative embodiment the upper corners of the guide rail members 40 are bevelled at 400: and the web and end-stop abutment means 35, 35:! projects upwardly between the bevelled portions 400. This arrangement facilitates the proper engagement of the end-stops and like elements between the rails 40 and with the stop abutments 35 and aids in assuring proper alignment of the parts.

Referring more especially to Fig. 2, the cooperating detent element means 39 in the form shown, comprises detent pins 39 with rounded or bevelled ends passing through openings in the webs of the rail members 49 adjacent the ends thereof. The pins 39 are in turn mounted on leaf spring members 39a seated in the channels of the rails 40 on the sides thereof opposite to those in which the home positions of alternate coupling and dog carriers lie, and secured therein by rivets passing through such webs.

When it is desired to change or replace a band 26 arranged as herein disclosed, it is not essential to remove the coupling and dog carrier at all, as the old band ends may be unhooked from the ends of the carrier, and the new band ends can be hooked over the pins 34a thereof with the coupling and dog carrier in place in the machine. This operation is facilitated by use of the simple tool shown in Figs. 5 and 6, comprising a narrow bifurcated tong 50, the bifurcated end of which is adapted to slip downwardly between the rails 40 and to grip the reinforced hook-end 26b of the band 26 as shown in Fig. 5. Shoulders 50a are preferably formed within the legs of the tong to abut against the upper edges of the members 26b, and on tightening the clamp screw 500, with the shoulders engaged, the hook end 26b is clamped against turning relative to the tool 50. It then becomes a simple matter to manipulate the tool as a handle from above the rails 40 to engage the hook 26a with the pin 34a below the rails. By the use of these tools it is possible to exert sufficient tension on a band relatively loosely trained about the rollers 27 to draw enough slack from the gentle bends thereabout to engage the hooks without actually backing off the rollers at all, but when desired or necessary, one or more of the sets of rollers may be released and backed off as described in connection with the endless bands of my previously mentioned Patent No. 1,982,991, to facilitate the hooking up of the non-endless bands of the present improvement.

From the foregoing description it will be perceived that the present improvements pertain particularly to a yarn traversing mechanism for a knitting machine of the type having yarn traversing bands forming elongated closed loops with curved ends, parallel forward runs in which the yarn carriers t2 are located and parallel rear runs in which the driving dog carriers 34 are located; that the present invention combines with the rear runs of the bands guiding and supporting means extending throughout the normal range of operation of the dog carriers, for supporting and guiding the dog carriers independently of the tension of the bands; that the guiding and supporting means more particularly comprises guiding rails that are flexible to enable disengagement of the dog carriers therefrom; that the guiding and supporting means advantageously are of channelled cross section with vertical webs and horizontal flanges defining mutually facing grooves, while the dog carriers advantageously comprise supporting webs positioned between the channeled members with laterally projecting runners, shown as ribs, entering the grooves between the flanges of the channels. Also it will be clear that the present invention provides the dog carrier with detent element means and the guiding and supporting means with cooperating detent element means for engaging the same, at one end of the range of travel of the dog carrier; that it provides the rail members with bevelled top edges,

and the dog carriers with end-stop engaging portions projecting therebetween, this arrangement aiding in maintaining the alignment with the end-stops. And in ad dition it is clear that there has now been provided an improved non-endless band with an improved coupling carrier and supporting means that facilitate placement and replacement of the bands.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that many modifications and changes may be made therein without departing from the essence of the invention. It is therefore to be understood that the exemplary embodiments are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

I claim:

1. In a yarn traversing mechanism for a knitting machine of the type in which the yarn carriers are in the form of flexible bands forming elongated closed loops having curved ends, parallel forward runs by which yarn feeding tubes are carried and parallel rear runs in which driving dog carriers are located for moving the bands; the combination with the rear runs of said bands of guiding and supporting means extending throughout the normal range of travel of said dog carriers, said guiding and supporting means comprising guide rails, said guide rails and dog carriers having interengaging guide channels, said rails being separable to disengage said interengaging guide channels.

2. In a yarn traversing mechanism for a knitting machine of the type in which the yarn carriers are in the form of flexible bands forming elongated closed loops having curved ends, parallel forward runs by which yarn feeding tubes are carried and parallel rear runs in which driving dog carriers are located for moving the bands; the combination with the rear runs of said bands of guiding and supporting means extending throughout the normal range of travel of said dog carriers, said guiding and supporting means comprising channelled members with vertically disposed Webs and horizontally projecting flanges defining guide grooves in the mutually facing sides thereof, and said dog carriers having supporting webs positioned between the channelled members with laterally projecting runners entering the grooves between the flanges of such channels.

3. A combination according to claim 2, said channelled members being flexible so that they may be sprung apart to release said dog carriers therefrom.

4. A combination according to claim 2, said dog carriers each having notch means therein facing one of said rails, and said rails carrying spring pressed detent elements positioned to engage in said notch means at one end of the range of travel of each dog carrier.

5. A combination according to claim 2, said channelled members having bevelled top edges at the sides facing said dog carriers, and said dog carriers having portions extending upwardly between said bevelled edges for engagement with end stop members entered between said bevelled edges.

6. In a yarn traversing mechanism for a knitting ma chine of the type in which the yarn carriers are in the form of flexible bands forming elongated closed loops having curved ends, parallel forward runs by which yarn feeding tubes are carried and parallel rear runs in which driving dog carriers are located for moving the bands; the combination with the rear runs of said bands of guiding and supporting means extending throughout the normal range of travel of said dog carriers, said dog carriers each comprising a first detent element means, and said guiding and supporting means comprising cooperating detent element means for engaging said first detent element means at one end of the range of travel of a dog carrier.

7. In a yarn traversing mechanism for a knitting machine of the type in which the yarn carriers are in the form of flexible bands forming elongated closed loops having curved ends, parallel forward runs in which bandcarried yarn feeding tubes are located and parallel rear runs in subcombination, a non-endless yarn traversing band and a detachable coupling carrier for joining the ends of said band, said carrier having slotted ends with pins traversing the slots therein, and said band having hooks at its ends enterable into said slots and engageable over said pins, said hooks being undercut to move outwardly after engagement with the pins for securing them against accidental displacement therefrom.

8. A subcombination according to claim 7, said band having reinforcing plates secured to the ends thereof in which said hooks are formed.

9. A subcombination according to claim 7, said carrier having an upstanding supporting web between its ends, said web carrying runner elements for engaging guide rails.

10. A subcombination according to claim 9, one of said runner elements comprising detent element means for engaging cooperating detent element means carried by a guide rail.

11. In a yarn traversing mechanism for a knitting machine of the type in which the yarn carriers are in the form of flexible bands forming elongated closed loops having curved ends, parallel forward runs .in which bandcarried yarn feeding tubes are located and parallel rear runs in which coupling and dog carriers are located; in subcombination, a coupling and dog carrier comprising means for attaching it to a band, said carrier having a supporting web extending upwardly above said band attaching means with-runner means in the form of longitudinal ribs extending laterally from said web for engagement with supporting channel means, said web extending upwardly beyond said ribs to form end-stop engaging means.

12. A subcombination according to claim 11, one of said longitudinally extending ribs having bevelled ends and having detent notch means spaced inwardly from said bevelled ends for engaging a cooperating detent element.

References Cited in the file of this patent FOREIGN PATENTS 643,264 Great Britain Sept. 15, 1950 

